1. Field of the Invention
The present invention relates to the field of connectors, more specifically to the field of high-speed connectors suitable for use in data transmission.
2. Description of Related Art
Connectors are commonly used to couple a communication circuit on a first circuit board to a communication circuit on a second circuit board. For example, a connectors system can include a plug and a receptacle, with the receptacle mounted to a circuit board and a plug mounted on an end of a cable.
As is known, increasing the distance that the signal needs to travel (e.g., using a longer cable) increases the difficulty of transmitting a signal. Signals become more attenuated as the cable lengths increase. In addition, higher frequencies tend to be attenuated more quickly in cables. Compounding this issue is the fact that greater lengths of cable tends to pick up more noise. As can be appreciated, therefore, decreasing the signal strength while increasing the signal noise will eventually make it so that the signal cannot be discerned over the signal noise. This natural occurrence acts to limit the length of cable that can be used.
To address the above issues, different communication protocols use different techniques to address the issue. Gigabit Ethernet, for example, which is intended to be run over twisted-pair, such as Category 5e or Category 6 cable, limits segment lengths to 100 meters and uses 5 level pulse amplitude modulation (PAM-5) to limit the need for high frequencies. 10GBASE-T (also referred to as IEEE 802.3an) also works over twisted pair but uses 16 level pulse amplitude modification (PAM-16) to achieve the higher data rates. Current connector designs appear to provide 55 meters with Category 6 cables and new cable (Category 6a) is being planned to allow the desired 100 meter segment lengths. The need to upgrade cable in order to provide 10GBASE-T, however, makes the upgrade path less desirable and therefore certain people would appreciate a design that could help enable 100 meter segments of 10GBASE-T over category 6 or even 5e cable. Further improvements would also benefit the system, potentially reducing the cost of transceiver circuitry.